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The assignment of phase center positions (in 2D or 3D) derived from SAR data to physical object is challenging for many man-made structures such as buildings or bridges. In contrast, light poles and traffic signs are promising targets for tasks based on 3-D geolocation as they often show a prominent and spatially isolated appearance. For a detailed understanding of the nature of both targets, this paper presents results of a dedicated simulation case study, which is based on ray tracing methods (simulator RaySAR). For the first time, the appearance of the targets is analyzed in 2D (image plane) and 3D space (world coordinates of scene model) and reflecting surfaces are identified for related dominant image pixels. The case studies confirms the crucial impact of spatial resolution in the context of light poles and traffic signs and the appropriateness of light poles as target for 3-D geolocation in case of horizontal ground surfaces beneath. [ABSTRACT FROM AUTHOR]

The city of Toulouse is a major contributor to the public visibility of Occitan, a regional language (RL) associated with southern France. Whilst French law recognizes the country's RLs in terms of national heritage, the official supremacy of French remains constitutionally unchallenged. This means that, along with other public texts, street names are only officially sanctioned in French. The bilingual street signs in central Toulouse recognize this hegemony by consistently displaying French above Occitan. However, they also suggest a covert preference for the RL, where Occitan overshadows French in the meaning associations of street names, and their translation and adaptation on the lower plaques. This challenges the linguistic hierarchy as determined by code preference, as Occitan emerges as a dominant code hidden in plain sight. This article proposes several methods for quantifying Occitan vitality as seen on street signs. Based on current notions of code preference and inter-text translation, it offers some new approaches to classifying and analysing multilingual signs in the Linguistic Landscape. [ABSTRACT FROM PUBLISHER]

Efficient and precise real-time video-based vehicles supervision systems for traffic surveillance are ever demanding. Developing an accurate detection and tracking algorithm by incorporating the effects of vehicles shadow or visual obstacles/occlusion including road signs, trees, or other vehicles is a challenging task. We propose a new approach for efficient detection and tracking of moving vehicles in the presence of shadow and partial occlusion under complex road scenes by combining the modified background subtraction and innovative adaptive search window methods. The use of variable-size window (Bounding Box) reduces the searching space proportional to the allocated time of the moving vehicles. First, a background model is constructed and then subtracted from subsequent traffic frames to distinguish the foreground objects (moving vehicles regions) and stable background regions. Finally, the shadow detection and occlusion handling between the moving vehicles are implemented to leverage the surveillance performance. The performance of the proposed method is benchmarked using baseline highway category of changedetection.net standard dataset having 1231 frames. Performance evaluation is carried out in terms of time complexity analysis, detection accuracy, and processing time. The experimental results demonstrate a radical reduction in computational time in terms of searched space. A superior detection accuracy (more than 99%), and processing time $$\sim $$ 29.6 ms (per frames in milliseconds) together with the time complexity degree of O( $$n^{2}$$ ), is achieved. Excellent features of these results suggest that the proposed approach is prospective for computer vision application and high-way traffic surveillance. [ABSTRACT FROM AUTHOR]

High-definition and highly accurate road maps are necessary for the realization of automated driving, and road signs are among the most important element in the road map. Therefore, a technique is necessary which can acquire information about all kinds of road signs automatically and efficiently. Due to the continuous technical advancement of Mobile Mapping System (MMS), it has become possible to acquire large number of images and 3d point cloud efficiently with highly precise position information. In this paper, we present an automatic road sign detection and recognition approach utilizing both images and 3D point cloud acquired by MMS. The proposed approach consists of three stages: 1) detection of road signs from images based on their color and shape features using object based image analysis method, 2) filtering out of over detected candidates utilizing size and position information estimated from 3D point cloud, region of candidates and camera information, and 3) road sign recognition using template matching method after shape normalization. The effectiveness of proposed approach was evaluated by testing dataset, acquired from more than 180 km of different types of roads in Japan. The results show a very high success in detection and recognition of road signs, even under the challenging conditions such as discoloration, deformation and in spite of partial occlusions. [ABSTRACT FROM AUTHOR]

This paper proposes a camera road sign system of the early warning, which can help to avoid from vehicle collision with the wild animals. The system consists of camera modules placed down the particularly chosen route and the intelligent road signs. The camera module consists of the camera device and the computing unit. The video stream is captured from video camera using computing unit. Then the algorithms of object detection are deployed. Afterwards, the machine learning algorithms will be used to classify the moving objects. If the moving object is classified as animal and this animal can be dangerous for safety of the vehicle, warning will be displayed on the intelligent road sings. [ABSTRACT FROM AUTHOR]

Roundabouts are internationally recognized as a viable alternative to signalized and stop-sign controlled intersections, and the frequency of roundabout implementations continues to increase. The safety advantages associated with roundabouts are often cited as significant reasons for the conversion of traditional intersection designs to roundabouts. Safety evaluations at real-world sites are costly and cannot be performed for evaluating alternative geometric designs unless those designs are actually built. Microsimulation that is commonly used for the evaluation of alternatives with regards to their operational performance can also be used for safety assessment. The Federal Highway Administration developed the Surrogate Safety Assessment Model (SSAM) that uses vehicle trajectories obtained through microsimulation to estimate the number of conflicts based on several surrogate measures of safety such as time to collision and speed differential. While SSAM has been extensively used for safety evaluations at other types of intersections, applications of SSAM at roundabouts are limited. In particular, a double single lane roundabout has never been evaluated using SSAM. The objective of this study is to assess the accuracy of SSAM in predicting potential number of conflicts at roundabouts that vary in their geometric design and traffic demand characteristics. In addition, a before and after study is performed to assess safety benefits when signalized intersections and stop-sign controlled intersections are converted to roundabouts. The results show that SSAM is an adequate tool for estimating the total number of conflicts, type of conflicts, and location of conflicts found from the real-world observations at both the single lane roundabout and double single lane roundabout. The before and after study showed that roundabouts significantly decrease the number of conflicts when signalized and stop controlled intersections are converted to roundabouts. [ABSTRACT FROM AUTHOR]

With increasing traffic and limited resources, the Florida Department of Transportation (FDOT) moves forward with a vision of optimizing intersection control using innovative intersection designs through the Transportation Systems Management & Operations (TSM&O) program. These alternative designs successfully eliminate the left-turn phase, which otherwise reduces the conventional intersection's (CI) efficiency considerably. This paper focused on the Crossover Displaced Left-turn intersections (XDL), also known as Continuous Flow Intersections (CFI). The XDL concept is best suited for intersections with heavy or unbalanced traffic volumes. There is little guidance on determining whether partial XDL intersections are adequate to mitigate the overall intersection condition or full XDL is always required. The primary objective of this paper was to evaluate the overall intersection performance in the case of different partial XDL designs compared to a full XDL. The study intersection in Orlando, Florida, is experiencing two heavy conflicting movements operating near capacity. The XDL alternative was investigated for 4 different designs. Also, the impact of increasing volume on the intersection performance was considered by modeling the unbalanced volumes with 10% increment resulting in 5 different traffic scenarios. The results showed that a partial XDL alternative proved to be effective and compared favorably to a full XDL. Significant throughput improvements were observed in the XDL scenarios at the higher volume level with increase in capacity of 25%, 30-45% reduction in delay for the critical movements, and 25-40% reduction in queue lengths. The analysis revealed how partial XDL design can improve the overall intersection performance at various demands, reduce the costs associated with full XDL and proved to outperform the conventional intersection. However, partial XDL serving low volumes or only one of the critical movements while other critical movements are operating near or above capacity do not provide significant benefits when compared to the conventional intersection. [ABSTRACT FROM AUTHOR]

Road signs are tools that provide crucial information to drivers about various roadway situations. Therefore, the present study aimed to assess the levels of ‘situation awareness’ held by drivers in relation to these signs. This study also assessed the relationship between dyslexia, road sign comprehension, and road sign situation awareness, thus building on the limited research in this area. Drivers completed measures of road sign comprehension and dyslexia. Drivers then completed three drives on a driving simulator; each followed by a probe containing queries about the perception, comprehension and projection of road signs seen in the preceding drive. Situation awareness was lowest at the level of projection. Further, dyslexia was negatively associated with road sign comprehension, and road sign situation awareness, suggesting that the disorder may be detrimental for multiple forms of road sign processing. Implications are provided in the form of a ‘SAFE’ driver training program that targets a holistic form of road sign processing which takes into account sign meanings in relation to both in-vehicle and outer-vehicle factors; thus encouraging proactive driver behaviour. [ABSTRACT FROM AUTHOR]

Street signs are an everyday part of our lives. Yet their language and form reveal important aspects of written English. The aim of this article is to open the reader's eyes to some common features of English street signs by looking at some of the signs in a typical street, Leazes Park Road in Newcastle upon Tyne. On one side of Leazes Park Road the buildings are three-storey nineteenth-century brick townhouses, on the other assorted modern brick and concrete offices, shops and clubs. It is a mixed street of dentists, offices, shops, restaurants, flats and clubs; its signs are typical of English city streets. The paper forms part of a research programme looking at street signs in England from different perspectives (Cook, 2013); a complementary short paper looks at the signs of the traffic junction in Leazes Park Road. [ABSTRACT FROM AUTHOR]

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In order to realize an identification system of traffic road signs in real time, the authors have developed a performed detection method of these signs in real time. This method, presented in this paper, is implemented in two modules. The first is a pre-processing module based on video stream processing technics and the second, based on the polygonal approximation digital curves, identifies areas that may contain road signs using the particularity of their colors and contours. All algorithms implemented in this work are developed under the programming language C / C ++ using OpenCV library. The results of tests, realized on real videos of the traffic signs, show the performance improvement of the method developed in this work in terms of rate and speed of detection. [ABSTRACT FROM AUTHOR]

The introduction of cyclists' "danger boards" in the United Kingdom in the 1880s established a new form of road sign aimed at private, mechanized transport that redefined ideas of safety on the road. This article explores the implications of this for established road users. In particular it considers the transfer of responsibility for erecting signs from private clubs to the state in the context of cycling's eclipse by motoring in the early twentieth century. It uses the design development of road signs as a marker of changing power structures in road use. [ABSTRACT FROM AUTHOR]